Sentinel Lymph Node Involvement by Epithelial Inclusions Mimicking Metastatic Carcinoma: A Diagnostic Pitfall.

BACKGROUND An epithelial inclusion cyst within a lymph node denotes a heterotopic phenomenon. Nodal epithelial inclusion cysts have been reported in a variety of anatomical locations including pelvic, abdominal, mediastinal, and axillary regions. While nodal melanocytic nevus (also known as nevus cell aggregates) is the most common heterotopic phenomena involving the axillary lymph nodes, the presence of benign epithelial inclusion cysts in axillary lymph nodes is a rare but well-reported finding.

Lobular breast carcinoma metastasis to skeletal muscle, two case reports diagnosed by ultrasound guided FNA with evaluation of the roles of interventional cytopathology.

Skeletal muscle metastasis from breast carcinoma is a relatively rare clinical entity. We report two cases of breast cancer metastatic to the skeletal muscle, diagnosed by ultrasound guided fine needle aspiration (US-FNA) biopsy done by interventional cytopathologists at an outpatient cytopathology center. Our two patients presented with lower anterior neck firmness and chest wall mass, respectively.